Abstract: The present invention provides a method for forming a refractory metal-intermetallic composite. The method includes providing a first powder comprising a refractory metal suitable for forming a metal phase; providing a second powder comprising a silicide precursor suitable for forming an intermetallic phase; blending the first powder and the second powder to form a powder blend; consolidating and mechanically deforming the powder blend at a first temperature; and reacting the powder blend at a second temperature to form the metal phase and the intermetallic phase of the refractory metal-intermetallic composite, wherein the second temperature is higher than the first temperature.

Abstract: Improved compositions are described for the protection of gas turbine parts at elevated temperatures. The compositions are of the MCrAlY type, wherein M is Nickel, or Nickel in combination with cobalt and/or iron. The compositions further comprise a lanthanide, a group 4 metal selected from hafnium, zirconium, titanium, or a combination of these, and optionally, a group 14 element selected from silicon and/or germanium. The combination results in improved Al retention properties. Also disclosed herein are articles comprising the coatings.

Abstract: A method for repairing a nickel-base superalloy article, such as a gas turbine stationary flowpath shroud having flowpath cooling holes therein that has previously been in service, includes the steps of providing the nickel-base superalloy article that has previously been in service; and applying a restoration to a surface of the article. The restoration is applied by the steps of providing a restoration nickel-base alloy, wherein the restoration nickel-base alloy preferably has no more than about 15 weight percent chromium and no more than about 0.01 percent yttrium, thereafter applying a restoration coating of the restoration nickel-base alloy to the surface of the article by a hyper-velocity oxyfuel metal spray process or a low-pressure plasma spray process, and thereafter heating the article with the restoration coating applied to the surface thereof to a sufficiently high temperature to diffusion bond the restoration coating to the surface of the article. The article is then returned to service.

Abstract: A method for repairing a nickel-base superalloy article, such as a gas turbine stationary flowpath shroud having flowpath cooling holes therein that has previously been in service, includes the steps of providing the nickel-base superalloy article that has previously been in service; and applying a restoration to a surface of the article. The restoration is applied by the steps of providing a restoration nickel-base alloy, wherein the restoration nickel-base alloy preferably has no more than about 15 weight percent chromium and no more than about 0.01 percent yttrium, thereafter applying a restoration coating of the restoration nickel-base alloy to the surface of the article by a hyper-velocity oxyfuel metal spray process or a low-pressure plasma spray process, and thereafter heating the article with the restoration coating applied to the surface thereof to a sufficiently high temperature to diffusion bond the restoration coating to the surface of the article. The article is then returned to service.

Abstract: Improved compositions are described for the protection of gas turbine parts at elevated temperatures. The compositions are of the MCrAlY type, wherein M is selected from nickel, or a combination of nickel with cobalt, iron, or combinations thereof. The compositions further comprise palladium, platinum, rhodium, or combinations thereof, hafnium, titanium, zirconium, or combinations thereof; and can further include silicon, germanium, or combinations thereof, wherein the composition results in improved Al retention properties. Also disclosed herein are articles comprising the coatings.

Abstract: A method for repairing an article comprises providing an article, providing a repair material, and joining said repair material to said article. The repair material comprises, in atom percent, at least about 50% rhodium; up to about 49% of a first material, said first material comprising at least one of palladium, platinum, iridium, and combinations thereof; from about 1% to about 15% of a second material, said second material comprising at least one of tungsten, rhenium, and combinations thereof; and up to about 10% of a third material, said third material comprising at least one of ruthenium, chromium, and combinations thereof. The repair material comprises an A1-structured phase at temperatures greater than about 1000° C., in an amount of at least about 90% by volume.

Abstract: A refractory composition is described, containing niobium, silicon, titanium, and at least one of rhenium and ruthenium. The amount of silicon in the composition is at least about 9 atom %, and the amount of titanium present is less than about 26 atom %, based on total atomic percent. Turbine engine components formed from such a composition are also disclosed.

Abstract: A method for evaluating the thermal exposure of a selected metal component which has been exposed to changing temperature conditions is described. The voltage distribution on a surface of the metal component, or on a metallic layer which lies over the component, is first obtained. The voltage distribution usually results from a compositional change in the metal component. The voltage distribution is then compared to a thermal exposure-voltage model which expresses voltage distribution as a function of exposure time and exposure temperature for a reference standard corresponding to the metal component. In this manner, the thermal exposure of the selected component can be obtained. A related device for evaluating the thermal exposure of a selected metal component is also described.

Abstract: A nickel-based braze composition is described, containing nickel, palladium, and restricted amounts of boron and silicon. The composition can also contain tantalum, titanium, and zirconium, as well as aluminum, chromium, and cobalt. A method for joining two metal components, using the braze composition, is also described. The braze composition can also be used to fill cracks or other cavities in a component, e.g., a gas turbine part formed from a nickel-based superalloy. Articles of manufacture which contain the braze composition are also described.

Abstract: An environmentally resistant coating comprising silicon, titanium, chromium, and a balance of niobium and molybdenum for turbine components formed from molybdenum silicide-based composites. The turbine component may further include a thermal barrier coating disposed upon an outer surface of the environmentally resistant coating comprising zirconia, stabilized zirconia, zircon, mullite, and combinations thereof. The molybdenum silicide-based composite turbine component coated with the environmentally resistant coating and thermal barrier coating is resistant to oxidation at temperatures in the range from about 2000° F. to about 2600° F. and to pesting at temperatures in the range from about 1000° F. to about 1800° F.

Abstract: A method for forming an article is described. The method includes the step of applying a precursor material to at least one surface of a mold structure for casting the article, and curing the applied precursor material. The precursor material includes facecoat-forming constituents which can be curably converted into a facecoat; and a protective coating-former for the article being cast. Molten material is then introduced into the mold structure, so as to come in contact with the facecoat formed from the cured precursor material. The molten material is cooled, to form the article. The cured precursor material, which is in contact with a surface of the cast article, is then reacted with the article, to form the protective coating on the surface of the article. Related mold structures are also described.

Abstract: A method for forming an article is described. The method includes the step of applying a precursor material to at least one surface of a mold structure for casting the article, and curing the applied precursor material. The precursor material includes facecoat-forming constituents which can be curably converted into a facecoat; and a protective coating-former for the article being cast. Molten material is then introduced into the mold structure, so as to come in contact with the facecoat formed from the cured precursor material. The molten material is cooled, to form the article. The cured precursor material, which is in contact with a surface of the cast article, is then reacted with the article, to form the protective coating on the surface of the article. Related mold structures are also described.

Abstract: A method for repairing an article comprises providing an article, providing a repair material, and joining said repair material to said article. The repair material comprises, in atom percent, at least about 50% rhodium; up to about 49% of a first material, said first material comprising at least one of palladium, platinum, iridium, and combinations thereof; from about 1% to about 15% of a second material, said second material comprising at least one of tungsten, rhenium, and combinations thereof; and up to about 10% of a third material, said third material comprising at least one of ruthenium, chromium, and combinations thereof. The repair material comprises an A1-structured phase at temperatures greater than about 1000° C., in an amount of at least about 90% by volume.

Abstract: An alloy, an article comprising the alloy, and methods for manufacturing and repairing an article that employ the alloy are presented. The alloy comprises, in atom percent, at least about 50% rhodium, up to about 49% of a first material, from about 1% to about 15% of a second material, and up to about 10% of a third material. The first material comprises at least one of palladium, platinum, iridium, and combinations thereof. The second material comprises at least one of tungsten, rhenium, and combinations thereof. The third material comprises at least one of ruthenium, chromium, and combinations thereof. The alloy comprises an A1-structured phase at temperatures greater than about 1000° C., in an amount of at least about 90% by volume.

Abstract: A device for measuring at least one property of a material sample is disclosed. The device includes at least one sensor element which is formed by a direct-write technique. The device can be an instrument for measuring strain in the sample, or for measuring other properties or attributes of a sample, such as temperature. A turbine engine disk on which components of property-measuring devices have been direct-written is also described. Methods of forming sensor elements for property-measuring devices are disclosed.

Abstract: A conductive element comprises a metal core and a coating, wherein the coating comprises at least one layer of aluminum, an aluminum alloy, an aluminide, silicon, a silicon alloy, a silicide, and combinations thereof, and wherein the at least one layer has a predetermined thickness. A method of making a conductive element comprises depositing a coating material on a metal core to form a coated metal core and heating the coated metal core to a predetermined temperature to form at least one layer of aluminum, an aluminum alloy, an aluminide, silicon, a silicon alloy, a silicide, and combinations thereof.

Abstract: Improved compositions are described for the protection of gas turbine parts at elevated temperatures. The compositions are of the MCrAlY type, wherein M is selected from nickel, or a combination of nickel with cobalt, iron, or combinations thereof. The compositions further comprise palladium, platinum, rhodium, or combinations thereof, hafnium, titanium, zirconium, or combinations thereof, and can further include silicon, germanium, or combinations thereof, wherein the composition results in improved Al retention properties. Also disclosed herein are articles comprising the coatings.

Abstract: Improved compositions are described for the protection of gas turbine parts at elevated temperatures. The compositions are of the MCrAlY type, wherein M is Nickel, or Nickel in combination with cobalt and/or iron. The compositions further comprise a lanthanide, a group 4 metal selected from hafnium, zirconium, titanium, or a combination of these, and optionally, a group 14 element selected from silicon and/or germanium. The combination results in improved Al retention properties. Also disclosed herein are articles comprising the coatings.

Abstract: A combinatorial process for production of material libraries from a single sample, comprising forming a diffusion multiple in the single sample, wherein the diffusion multiple comprises a plurality of interdiffusion regions at interfacial locations of dissimilar metals, metal oxides, or alloys, and wherein the diffusion multiple comprises at least three layers of the metals, non-metals, metal oxides, or alloys; and evaluating properties of the diffusion multiple as a function of composition at about the interdiffusion regions.

Abstract: A nickel-based braze composition is described, containing nickel, palladium, and restricted amounts of boron and silicon. The composition can also contain tantalum, titanium, and zirconium, as well as aluminum, chromium, and cobalt. A method for joining two metal components, using the braze composition, is also described. The braze composition can also be used to fill cracks or other cavities in a component, e.g., a gas turbine part formed from a nickel-based superalloy. Articles of manufacture which contain the braze composition are also described.